Electrical connector.



,2 'iquently removed andreplaced, it results in a twisting and knotting of the connecting coi-d, particularly if the cord is short and teeteee Tora/.ZZ ,fw/mm t may concern.'

VBe it Vknown that I, JOHN CUTHBn-n'r, a .citizen .of the United States, residing at Chicago, in the .county of Cook and State oi'V Illinois, have invented certain new and usetuhlmprovements in Electrical Connectors, ol vwhich the following is a specfica` tion. `rl.-This invlnition relates to improvements in electrical .connectors and more particularly Vto a plug connector for insertion in a screvv ,socket of thelconimonly used Edison type.

1A Well recognized disadvantage of the Iusual `iormof screw plug orscrew hase is thatfitrequires,several complete revolutions .beforethe end Contact seats against the bottom of theV socket'.V` This is not only an annoying andjtlme-consumlng operation, but :in Inanyinstances,"vhe1e the plug is treits other end x'ed;

llt is the object of my invention to overhcone' tlie'` disadvantages inherent in the A ab'ove described plugs.

'..l The particular object of the invention is tqprovide a` plug which may be firmly seated jin" the common type of screw shell socket by pushing'the Vplug aijially into the socket and giving it a lpartial yturn to lock it in place.

v The operation of inserting my improved plug in' a.` socket isv very similar to that per.n

formed connecting an Edi-Swan plug, the

Edi-'Sivan plug being adapted, of course, for

connection only `with an Edi-Swan socket,

Whereas my plugmay be used in the com- ,nion type of screw shell socket.

I' .iin additional `object of my invent-mn 1s 40.-

' part madein one piece and which may be the construction oa plug, having a body wired lWithoutl the Vremoval or detachmen `=of any parts.

Other objects of my invention are to simplify the construction of electrical connector j 'plugs increasing their e'Iiiciency and reducing the cost of manufacture.

.Still further? objects and advantages' in- Lcidentto my' invention will become appar eiity'tofthose skilled in the art from a consideration the following description and 'draivings whereinf ,"Q'Figure l visa side elevation ot' my 1mproved plug showing a double cord connect ed thereto.l "Fig, 2 is a vien' of the sanne.

lltllhl' CUTHBET, 0l? CHECAGG, ELLIN'ES.

Specification of Letters Patent.

Application tiled March 1916. Serial No. 82,792.

is performed. vthe central axially movable contact in- ELEGTBAL GGNNEVTOR.

atented May 29, igt 7,

Fig. 3 is a dianieti'ic sectional view on the line 3-3 of Eig. 2, showing the plug in'- serted in a socket. y'

Fig. 4; is a diametric section on the line -l ot Fig. 2, showing the plug inserted in a socket.

Figs. 5, 6 and 7 are detached perspective views ot the Wedge block,` and the tvvo 'screw sectors. f

Fig. S is a fragmentary sectional View similar .to F ig. 3 showing the position occupied by the parts when theV plug is removed- 20. of insulating material, having at its end a centrally located axially movable contact member 21, and at diametricall'y opposite points on its periphery metallic screw sectors or segments 22, 23 for Contact iviththe shell 24 of a receptacle '.ifiescrew sec-` tors 22, 23 are radially movable with. respect to the body ofthe plug and aree-onf nected mechanically in such a Way with the axially movable center Contact 2l, though electrically insulated therefrom, that when the plug is seated `vith its inner endvagainst y i the bottom of asocke't the axialmovement of the central contact 21 Wedges the screw sectors outwardly into tight contact with the socket shell 2l, after which a slight rotation ofthe plug, screws the plug into the receptacle a suicient distance to tightly lock it in place. The farther in. the plug is screwed, the tighter the screw segments arf forced outwardly against the socket shell.

To remove the plug the reverse operation A spring 26 serves toi-.move

Wardly, consequently drawing the screw segments radially toward the axis of the plug and out of Contact With the shell, so that after about a. quarter of a revolution the plug is free to be drawn axially out of the socket.

Jlhe above is a general outline of the func.

, the preferred embodiment of my invention,

V.formed on its outer i substantially that of the rectangular which is illustrated in Figs. 1 to 8 inclusive, 1 will now describe the same more in The body part of the plug indicated by the numeral 20 and formed of insulating material, such as porcelain or a non-conducting composition, such as bakelite, is of generally cylindrical outline through its major portion 27, whidh is that part of the plug adapted forinsertion within a receptacle and which I will subsequently refer to as the inner end. A sufficient distance from the inner end of the plug, Vso as not to interfere with the proper seating of the plug within abnormally deep sockets 1 have formed a projecting annular shoulder 28, beyond which the outer or rear end of the plug is squared as at 29, so that the operator may iirmly grip the same with his fingers.

A diametrically disposed. slot 30 of generally rectangular cross section is formed in the cylindrical body portion ofthe plug 27 near .its inner end to receive parts ofthe radial movable screw segments v22, 23, Aand the operating device, by means of which axial movement of the central contact 21 is converted into radial movement oi the two segments..

Though a mechanical connection exists between the screw segments and the central connector, it is essential that there be .no

electrical connection, and with this end in view, 1 have provided a generally rectangular block 31 of insulating material, shown in perspective in Fig. 5, to serve as the connecting medium. The block is of a width slot 30, although its length. and height are considerably less than the corresponding dimensions of the slot. inwardly inclined slots 32-32 are cut from the upper outer corners of the rectangular block 31I to make connection with the screw segments 22, 23. Each of the screw segments comprises a vertical portion 33 having screw threads tace to correspond with the screw threads of the receptacle shell 24. Each sector also has an inwardly extending leg 34 at right angles to the screw threaded -portion projecting from the lower edgeslot V32P-32', in the block 31. To facilitate the assembling of the device 1 have made one of the screw segmentslthat shown in Fig. 7) of a width approximately equal to the width of the slot 30 in the body part of the plug so that after the 4two screw seg ments are positioned with respect to the insulating block 31 the assembled parts may be slid into the slot from one end, the 'side wings 33 of screw segment 22 which exlment taking the Leemans tends beyond the sides of the slot 30 overlying the periphery osthe plug portion 27 and serving as additional frictional surface for contact with the receptacle shell. When assembled in position it is obvious that axial movement of the insulating block 31 results, through the action of the inclined slots 32 on the wings 35, in outward 0r inward radial movement of the two screw segments, 22, 23.

- An axial opening in which is inserted a bushing thimble 36 extends from the transverse slot 30 through .to the center of the inner end of the plug, the end contact which I have heretoforev referred as being designated by the numeral 21, in this embodi- Eorm of a screw, the head of which serves as a contact and the shank portion 37 of which extends through the bushingthimble 3G and into screw threaded engagement with ha tapped opening 38 inv the center of the insulating block 31. From this, it will be obvious that axial movement of the central contact 21 is converted into radial movement of the screw segments 22, 23, axial inward movement of the` connector causing outward movement of the sectors by pressure clined slots 32 against the inclined wings 35, the reverse spring induced movement of the center contact drawing the screw segments irnvardly toward the center of the body part of the plug, and out of engagement with the screw threaded shell 24.

As a means of connecting an electric cord with the plug 1 have provided an axial bore 39 in the outer end of the plug extending to a depth approximately equal to the, depth of the squared outer portion, into which the ends ot' the wires may be led. Leading from the axial opening 39 are two smaller bores 40, 41, which carry the individual wires to their respective terminals. The bore 40 extendson a line that would approximately intersect the inner edge of the plug, terminating however in a recess 42 formed in the inner end of the plug to receive a connector bar 43, one end of which is provided with an opening through which passes the thimble 3G, to which it is clamped by the thimble head 44. The connector bar 43 in its other end is provided with an opening 45 registering with the wire carrying bore 40, through which the wire 46 may be passed and clamped under the rim oi the connector screw '47, which takes into the connector bar 43. To insure thegoutward axial movement of the contact 21 when the plug is unscrewed and to insure proper release of the screw segments 22, 23, from engagement with the socket shell,1` have .'provided a U-shaped spring member 26, one end of which is provided with an'opening to surround the barrel of the thimble 36 and underlie the conof the upper faces of the ini' hector-bar 43. I The other end extends radially outwardly in a continuation of the recess 42v andy then is turned back upon itself and provided with an opening through which the shank 37 of the screw 21 takes, the free end thus underlying` the head of the screw'21 and tending to resiliently press it outwardly away from the plug.

The other wire carrying bore 41 extends outwardly at a greater angle to the axis of the plug than bore 40, and terminates in a recess 48 cut in the side wall of the cylindrical portion 27 of the plug at a point approximately midway circumferentially between the two segments 22, 23. An aperture 49 connects the recess 48 and slot 30, and is substantially filled by a connector strip 50 which lies against the central inner wall of the Aslot 30 and extends through the opening '49 and over the base wall of the recess 48.

The connector strip 5() is held in position by a. screw 51 which takes axially through the base of the opening- 39 formed in the 'rear' end of the plug and into the inner end of the strip, as at The outer end of the strip is provided with an opening registering with the wire carrying bore 41 and through which the wire 53 may be passed for connection with the clamping screw 54. The inner legs 34-34 of the screw segments 22,

- 23, overlie the inner end of the connecting strip 5() making electrical Contact therewith and serving as a connection between the wire 53 and the shell of the socket lwhen the plug is in place. To insure a positive connection between the inner legs 34-34 and the connector strip 50 I have beveled ofi the inner ends of these legs, as at 55, for engagement with a' projecting Wedge shaped nub 56 on the inner end of the block 31 so that when the plug is in place and the block firmly pressed inwardly to its Wedging position, the projecting nub 56 engages the i Inthe presence lating material having a transverse opening therein, a pair of oppositely positioned contact members slidably positioned in said opening, one of said members havinga Width less than the width of the opening for passage therethrough, the other having a portion Wider than the opening to overlie the edges thereof and the exposed surfaces of said members having screw threads formed thereon, a contact positioned at the inner end of 'the plug and axially movable with respect thereto, and a block of insulating material positioned within the opening andengaged by all the contact members for transmitting movement of the axially movable contact to the slidable contacts.

2. In an electrical connector plug the combination of a cylindrical body part of insulating material having a transverse opening extending therethrough, a pair of oppositely positioned contact members each having an inturned base portion for sliding contact with a wall of the transverse openingA and an inturned angularly disposed wing, a contact positioned at the inner end of the plug and axially movable with respectthereto, and a block of insulating material positioned within the opening for axial movement with the central contact, said block having singularly disposed slo'ts for engagement with the angularly disposed wings of the contacts.

3. In an electrical connector plug the combination of a relatively fixed cylindrical body1 part of insulating material having a transverse opening therein, a pair of oppositely positioned Contact members each vhaving an inturned base portion and anangularly disposed top portion slidable transversely of the axis of the plug in said opening,.a block of axially movable insulating material positioned within the opening and engaging the contact'members to move 'the same radially when the block is moved axially and a pin carried bythe block and extending axially thnough the plug to the inner end thereof and having a head formed on its inner end to provide a central contact.

In testimony whereof I hereunto se't my hand in the presence of two subscribing witnesses.

OHN CU'II-IBERT. O STANLEY W. Coon, MARY F. ALLEN. 

